I took a fly swatter to coffee today. We sit by the door and it is full of flies. Every time my knowledgeable friend went into his monologue that included the details of how many eggs his wife cooked for breakfast yesterday as well as today, I swatted an imaginary fly on his shoe. He had to breathe and someone else jumped in.

I never managed that one myself.

You could try interjecting that story you told recently about the younger man. That was quite a gobstopper.

I have two of my work daughters that kept doing this the first 2 years of working under my wings .
I loved them both and they are young , one was 27 at the time and the other 29. Man , non stop talking and non stop interrupting and non stop making it all about them every x .
Now , bcz I care about those ladies and I don’t want them to act like idiots and be a burden at their circles , I had no problem to be brutal .
I told them both at diffent x , “ cut it out mouth “. Stop . Just stop “. And later I told each one y this is something that they need to eliminate . They were young and smart and I wanted to see them to succeed . And success is not just degrees and certifications and money and blah blah . It’s manners and communication w humans . They hated me for about 15 mnt , but both / years later have developed great conversation skills and I see the progress and I am happy for them .
If these people are worthy to u , tell them . If not , avoid and let them be Lora . That’s my humble advice .

I had one friend in particular that behaved that way, and no matter what someone said, she would hijack the topic and start talking about herself.

I imagine it's some type of emotional tick that would make her persist beyond me attempting to disengage several times. As you mentioned, other friends would stop joining us, so I eventually ended the friendship. I wish I could offer a better solution.

You neglected to mention who bestowed upon you the authority to moderate conversations.

Try just interrupting, politely

My ex-husband Terry has diarrhea of the mouth. He's a retired teacher.

I just raise my hand. Terry shuts up and calls on me.